Boiler construction



April 3, 41934.

T. M URRAY BOILER oigsTRUcTIN original .Filed Dee.4, 1923 v 3 sheetshet-1 Snoamtoz .......unmwnmmnuww MU RRAY April l3,111934.- TQ E.

' BOILER CONSTRUCTION Original Filed Dec. 4, 1923 5 Sheetshee't 2;

April 3, 1934- T. E. MURRAY 1,953,76@y

BOILER CONSTRUCTION l original `Filed Dee. 4. 1923 asheets-sheetPatented Apr. 3, 1934 UNITED s'rivras Thomas E. Murray,` Brooklyn, N.Y.;

PATENT@ oFFlce Y Bradley Murray, .John F. Murray,

Murray, deceased,

executors of said Thomas E. assignors to Metropolitan EngineeringCompany, acorporation of New York .. Application December 1923, SerialNo. 678,443

Renewed November 23, 1932 1i)` Claims.

A The present invention provides a special con struction of boiler walland arrangement of tubes for use in various installations `in whichboiler tubing is arranged alongside a wall.

The accompanying drawings illustrate embodiments of the invention. Fig.1 is a vertical section of one of the boiler walls;

Fig. 2 is an inside elevation of the same, partly in sectionapproximately on the line 2--2 of Fig. 1;

Fig. 3 is a section similar toFig. 1 at another point in the wall;

Figs. e and 5 are enlarged details oi Fig. 1;

Fig. 6 is a section on a larger scale showing a modification of Fig. 3;

Fig. 7 is a side elevation,'partly in section showing the connections ofthe different sets of tubes;

Fig. 8 is a cross-section oi an alternative detail.

Referring to the embodiments of the invention illustrated, the structureis supported by side co1- umns 1 carrying at their upper endscross-beams 2. in the upper part of the boiler, supported and arrangedin the usual or any suitable way, are the boiler tubes- 3-a`ndsuperheater tubes 4. These are enclosed with-in a shell of sheet metal5, 6, supported from tire columns and lined with tile, fire-brick orother insulating material 71. Below the boiler elements described andenclosed by the side and end walls is the space 8 which constitutes thefurnace or chamber through which the heating gases rise. Exposed at thesides of this chamber are the supplementary tubes 9. These tubes areprovidedwith flanges 10 between them and overlapping so' as to close thespaces between the tubes, such flanged tubes being described in certainprevious patent applications of mine. This lowerpart of the boiler wallis simi.-

Vlar to the upper-part, comprising plates 1i)a of sheet metal on theoutside lined with insulating blocks 11 and rire-bricks l2, againstwhich .the tubes 9 are located.

t -The tubes 9 runat their upper ends into a header 13. which issupported at intervals by straps 14 suspended by rods 15 and channels 34from the overhead cross beams 2. At their lower ends, they enter a lowerheader 16 or mud drum, The usual connecting tubes for circulation of thewater are assumed and-they may be arranged and located in any suitableway.

' Where the wall is pierced with a door 1'? in line with the tubes across-box' 18 is provided connecting the tubes above with short tubes 19passing down alongside the door to the lower header 16. The lowerportions oi the tubes, up to a point some distance above the level ofthe tops of the doors, is protected by an inward horizontally extendingportion of the Wall consisting of a layer of insulating material 20 toprotect the joints oi the tubular structure. The cross-box 18 is set ina casing 21 in this lower part of the wall, the casing being largeenough to permit a certain vertical movement of the cross-box. The lowerpart of the wall, below the level of the doorway, includes a plate-22backed at intervals by a casting 23 which is channeled and ribbed asshown. The plate 22 is perforated at points which are engaged by thecasting 23. Air is supplied through a pipe 24 and passes through thechannels of the casting and thence through the plate 22 into the furnacen chamber for combustion. The lower header or mud drum 16 is locatedback of the plate 22 and in such a position as to be capable of verticalmotion. The bottom wall 25 and its facing 26 are supported on thefoundations of the structure and carry the` plate 23 and the lowerportion 20 of the wall, with the casing 21; and these parts in turncarry the intermediate portion of the wall composed of the outer plates10a and the lining 11 and 12. l

The purpose of the lining of insulating material 20 is not only toprotect the joints and other parts of the tubular structure, but is alsoto protect the fuel against such cooling as would retard combustion.This protecting wall 20 is high enough to prevent the'tubular structurefrom absorption of Iheat so rapidly from the reebed as to interfere witheicient combustion. This protecting wall serves the same purpose whetherthe furnace be used for a boiler or for any other purpose. The back ofthe tile or other material of which the wall 2li-is composed, is cooledby the water circulating through the tubes sufiiciently to prevent toorapid burning out of the wall. rilhe upper header 13 is enclosed in ametal box illustrated in detail in Fig. 5. This box comprises sideplates 27 and 28 and a top 29 on which the upper part of the wall issupported. The bottom of the box consists of plastic material 30 whichis enclosed between side plates 31 and 32 of tile which rest on tiles 33supported on the top of the intermediate wall (11 and l2). The bottom ofthe box thus constituted is adapted to move upward, sliding between thesides of the box, when the wail on which it is supported is moved upwardunder the expansion produced by the high temperature. Thus theintermediate part of the wall, when subjected to the heat of the gaseswill expand upward, being solidly supported on its foundation, (and suchexpansion will be taken up within the box which encloses'the upperheader i'or these tubes. The intermediate part of the side wall is notfastened to the main supporting columns 1. The upper part of the wall iscarried by a beam 35 which is carried on the inner faces of thesupporting columns 1. The upper section of the wall is practicallyiixed, though it can expand slightly. But the greatest heat comes on thelower part of the wall and the actual extent of the expansion will begreatest for this section of the wall. v

'Ihe arrangement illustrated also permits expansion of the side tubes 9.This expansion will be greater than the expansion of the wall and' willbe in the opposite direction, that is downward. It is for this purposethat the cross-bar 1S and the lower header or mud drum 16 are supportedmerely by the tubes themselves and are arranged in recesses or casingsof the wall which permit a relative downward movement of the cross-boxand the lowerv header,relative to the wall.

It has been explained that the joints in the lower portions of the tubes9 are protected from the heat inthe lower part of the furnace chamber bythe wall 2O on the inner side of such tubes. To prevent cooling of thecross-box 18 and also the lower header 16 by the outside air, they maybe packed in yielding insulating material. As shown in Fig. 4, the box21 is made up of a casting open at the outer side and with a plate 36 onthe inner side protected by the insulating wall 2o. The casing for thelower drum is formed of the plate 22, the bottom of the casting 23, atop plate 37 supporting the brickwork of the doorway and a channel 38depending from the air cooled frame 39 of the doo According to thedesign of Fig. 6, the construction is simplified by using a casting 40which is perforated for admission of air and omitting the covering plate22 or Fig. 4. The casingin either case may be closed on the outside by aplate such as 41 and air introduced through a pipe 42. Fig. 8 shows analternative arrangement n which cooling oi the header 16 is prevented bya filling of occulent insulating material 38EL held in place by a block38h of masonry.

The bottom constructions described are useful particularly for powderedcoal furnaces, or they' may be used for Stoker-fired `furnaces or ioroil or gas fired boiler furnaces; and in fact, for many furnaces notnecessarily used in connection with boilers.

Fig. '7 illustrates in side elevation the various groups of boiler tubesand shows the manner in which the;7 are connected to each other and inwhich the water and steam are circulated; the walls and supporting partsof the structure being omitted so that the arrangement of the tubingwill be clear.

The vertical tubes 9 which extend alongside of and adjacent to the sidewalls and shield the latter are connected toa header 16 at their lowerend and to header 13 at the upper end. The steam generated thereinpasses out of one end of the header i3 to a vertical pipe 43 and thenceto a main steam drm 44. Thewater in this drum passes down by pipes 45 toheaders 46 at the lower ends of the upper series of boiler tubes, theinclined, approximately horizontal, tubes 3 previously referred to. Attheir opposite and higher ends, these are connected to headers 47 whencethe steam passes by vertical pipes 48 and horizontal pipes 49 tothe maindrum 44. At the -lower ends oi the headers 4.6 they are connected to across-header 50 which at its, OPPOS? ends connects with downwardlyinclined pipes 51 leading to the bottom headers 16 of the rst set oftubes 9. Thus the main drum 44 is in the circulating system of both setsof boiler tubes.

The steam from the drum 44 passes out of the top by a pipe 52 and thencedownwardly by a pipe 53 to a cross-header 54 at the lower end of thesuperheater tubes 4, which is the third set of tubes in the completeboiler. The superheated steam passes out to across-header 55 and thenceby way of a valve 56 to the superheated steam pipe 57. i

The invention is applicable to boilers having various other arrangementsof tubing and circulating connections.

The combination of the upright'tubes with the sheathing and withsuspending means located outside of the furnace is illustrated morefully and claimed in pending application Ser. No. 61,- 387, filedOctober 9, 1925.

Though have described with great particuvlarity of detail certainembodiments of my inclosely adjacent to the same so as to shield saidwall and exposed tothe radiant heat of the burning fuel on their innerside only, said wall having an inward horizontally extending portionthrough which the ends of the tubes pass said ends being free to movewith respect to the wall.

2. A structure of the character described including in combination aboiler` wall of masonry and a line of boiler tubes supportedindependently oi? said wall and alongside of and closely adjacent to thesame so as to shield said wall and exposed to the radiant heat of theburning fuel on their inner side only, said wall having an inwardhorizontally extending portion through which the lower ends of the tubespass and said tubes being supported at their upper ends and free attheir lower ends to expand downwardly.

3. A structure of the character described including in combination aside wall, vertical boiler tubes. alongside or said wall and supportingmeans for their upper ends leaving them free to expand downward, a lowerheader suspended from the lower ends of said tubes and a casingextending inwardly from said Wall and enclosing said lower header and inwhich the latter is vertically movable.

4. A structure of the character described including in combination asidewall, vertical boiler tubes alongside of lsaid wall, a header fromwhich said tubes are suspended with freedom to expand downward, a lowerheader suspended from the lower ends of said tubes, and casingsextending inwardly from said wall and in which said headers ltermediatepoint in the length of said boiler tubes,

and connected above and below with parts of said tubes and free toexpand therewith, and a wall Carrying .9.- aSing enclosing saidcross-box with weaves a lower wall and a set of upright water tubesalongside of the same, said lower wall and upright tubes being supportedindependently of each other and being expansible one with relation tothe other and the lower wall being supported independently of the upperwall and being expansible with relation to the upper wall.

7. A structure including in combination an inner wall comprising a lineof upright water tubes space d apart with metallic extensionssubstantially across the spaces and extending over substantially thefull exposed length oi the tubes, and an outer wall supportedindependently oi said inner wall, the two'being close together to`prevent the passage of the heating gases between Vas.

them and so that the tubes are exposed to the heating gases onlyon theinner faces thereof.

8. A structure including in combination an inner Wall comprising a lineof upright water tubes spaced apart with metallic extensions extendingsubstantially across such spaces and an outer wall of masonry spacedaway from said ilanges and shielded from the heating gases oversubstantially -outer walls being close the inner and together so as to'prevent access of the heating gases between them and so that the uprighttubes are exposed to the heating gases on their inner faces only.

9. A structure including in combination an inner wall comprising a lineof yupright water tubes spaced apart with metallic extensions extendingits entire face by said inner wall,

substantially across such spaces and an outer wall of masonry spacedaway from said iianges and shielded from the heating gases its entireface by said inner wall, the inner and outer walls being close togetherso as to prevent over substantially access of the heating gases betweenthem and so that the upright tubes are exposed to the heating gases on'their inner faces only, and a protecting shield on the said uprighttubes.

l0. A furnace including an outer wall of refractory material on theinner side of which is a single line of upright water tubes and on theinner side of the lower portion of which is a protecting wall ofrefractory material, said tubes being spaced apart and metallic membersbridging the space between them from the top of the inside refractorywall to about the upper ends ofthe tubes, said outer wall being spacedfrom said metallic members. THOMAS4 E. MURRAY.

inner side of the lowerportions of y lll

